Art of producing molded pulp articles



Feb. 6, 1934.

M. P. CHAPLIN 1,946,437 ART OF PRODUCING MOLDED PUL; ARTICLES F iled Oct. 13, 1928 4 Sheets-Sheet 1 J75; 0e 7? 01': mark? 1? Chap u 71 Feb. 6, 1934. M P, HAPUN 1,946,437-

ART OF PRODUCING MOLDED PULP ARTICLES Filed Oct. 13, 1928 4 Sheets-Sheet 2 1710671 for Merle 671a la??- y Feb. 6, 1934. M. P. CHAPLIN ART OF PRODUCING MOLDED PULP ARTICLES 4 Sheets-Sheet 3 Filed Oct. 13. 1928 Feb. 6, 1934.

M. 'P. CHAPLIN I 1,946,437

ART OF PRODUCING MTJLDED PULP ARTICLES Filed Oct. 13, 1928 4 Sheets-Sheet 4 J I I. v In'vejfloif 77767Z I. Chapl. '77

fltai'izeg I v Patented Feb. '6, 1934 UNITED STATES ART OF PRODUCING MOLDED PULP ARTICLES Merle P. Chaplin, 'Waterville, Maine, assignor, by mesne assignments, to Fidelity Trust Company, trustee, Portland, Maine, a corporation of Maine Application October 13, 1928.

21 Claims.

In my present invention, which involves in part a carrying forward of some of the features of the invention illustrated, described and claimed in my prior application, Serial No. 265,551, filed March 21, 1928, I propose bothto form and dry molded pulp articles on a single machine and as part of a continuous operation by the introduction of a drying phase into what has heretofore been considered as a pressing phase in the cycle of the machine.

As contemplated herein, the articles are die molded from liquid pulp during the forming phase of the machine and are transferred from the forming dies directly to a series of drying dies where they are dried during 'a subsequent phase of the machine.

For the purposes of this application, I shall illustrate my invention in its adaptation to a series of rotating forming dies.

the formed articles are directly delivered from the forming dies for drying. These drying dies may be heated in any suitable manner to effect drying of the formed articles while in orbit thereon and the articles themselves may be retained on such dies during their orbit and dislodged therefrom on completion of such orbit in any suitable manner.

In the accompanying drawings I have shown several methods and several forms of apparatus for accomplishing these results.

In such drawings:

Fig. 1 is an end elevation partly in section of a pulp molding machine equipped with one form of my invention.

Figs. 2, 3, and 4 show modifications thereof, and

Fig. 5 is a detail showing a strip or web of connected articles produced on the machine of Fig..

4 prior to severing the individual articles from -the strip.

' In accordance with my general concept, the articles are molded on'forming dies 1. The pulp may be deposited on these dies in any suitable Serial No. 312,244

As is usual in this type of machine the forming 80 dies are equipped with mechanism for maintaining a vacuum therethrough during the initial phase of their revolution so as to take up a quantity of pulp suflicient to form the ultimate article together with mechanism for automatically discontinuing the vacuum and sending compressed air through the dies during a subsequent phase of their revolution whereby to permit transfer of the formed articles to a set of pressing dies rotating in properly timed relation to the forming dies and in an orbitally intersecting path.

As contemplated herein, however, I introduce into the cycle of the machine at this point a drying phase during which the formed articles are transferred directly from the forming dies to heated drying dies 3 whereon they are dried while in orbit and as a part of the continuous operation of the machine. Functionally these drying dies serve not only to dry the articles but have a pressing relation to the forming dies at the mo-.

ment of transfer of the formed articles'thereto whereby to assist in bringing them to ultimate article shape. They maytherefore be said to he dies of double function in that the article is both pressed and driedthereby and thereon.

As here shown, the dies 3 are-arranged in circumferentially spaced relationship about the periphery of a rotating die carrier 4 which revolves about an axis 5 parallel to the axis of rotation of the forming dies 1. is relatively greater than that of the forming die carrier so as materially to prolong the time of drying travel of the articles on the drying dies. The dies themselves are heated in any suitable manner, as by steam, hot air, electricity, or any articles transferred thereto from the forming dies are held thereon through an initial phase 01 the revolution of the drying dies and are automatically discharged therefrom during a subsequent phase while the vacuum is on it not only holds the articles on the drying dies but assists to carry away the moisture given off by'the articles as they are drying. v

- For the purposes of this application, however. I have shown the dies 3 in certain of the figures of the drawings as solid and have arranged in 00- The diameter of such carrier 90 operative relationship therewith either mechanical or pneumatic means for positively holding the formed articles thereon during the drying orbit and for positively discharging them therefrom at the completion of the drying orbit.

Referring now to Fig. 1 the forming dies are preferably of curved form as indicated at 1' so that when engaged by the drying dies 3 they contact over their entire surface. This results in the article being formed in a curved section, the curvature of the article being later straightened out on the heated drying dies 3.

The formed articles remain on the drying dies throughout substantially the entire orbit of the dies. Any suitable means may be employed for holding the articles on the drying dies while in orbit. When the drying dies complete their orbit, the dried articles discharge therefrom onto a conveyor 6 which may carry them to the point where they are to be stacked, counted and packaged, or if further drying is desirable such conveyor may first carry them through a drying tunnel of usual form.

Where the dies are solid the discharge of the formed and dried articles may be effected at the end of the drying orbit of the dies by means of a pair of revolving brushes 6 or equivalent stripping means. These strippers are arranged in the path of the articles on the drying dies for successive contact therewith as the dies are revolved therepast and positively dislodge the formed and dried articles therefrom onto the conveyor 6.

In the form of my invention shown in Fig.- 2 the general principles of the machine shown in Fig. 1 are followed with these differences; that in Fig. 2 the forming and drying dies both revolve with a step-by-step motion and between each step or pause in their motion the forming dies are moved towards the drying dies to bring the vdies into engagement with each other and to transfer the articles from the forming to the drying dies, and the surfaces of the forming dies are not made as curved sections but instead the surfaces of both the forming and drying dies are made straight. As an obvious reversal the drying dies rather than the forming dies may have this intermittent reciprocating motion imparted to them. Any suitable mechanism may be employed for imparting this timed intermittent rotation to the forming and drying dies and this timed intermittent reciprocation of the forming dies relative to the drying dies.

As here shown, such mechanism includes a shaft 7 driven from any suitable power source and provided with a pair of eccentrics 8 and 9. The,

eccentric 8 is linked at 10 to an arm 11 loose on the axis shaft 5 of the drying die unit and provided with a pawl 12 cooperating with a ratchet 13 fast on such shaft, and the eccentric 9 is linked at 14 to an arm 15 loose on the axis shaft 1" of the forming die unit and provided with a pawl 16 cooperating with a ratchet 17 fast on such shaft.

. The ratchets 13 and 17 are so proportioned to and at its opposite end constitutes a journal or bearing for the axis shaft 1 of the forming die unit.

By this. mechanism, the forming die unit is bodily moved intermittently towards and away from the drying unit in timed relation to the rotation of such units.

Any suitable means for holding the formed articles on the drying dies while in orbit and for effecting their discharge at the end of the drying orbit may be employed. When dislodged the formed and dried articles may discharge into a packaging chute 24'.

In the form of my invention shown in Fig. 3 the drying dies may be solid, and I propose to assist the drying action on the heated drying dies 3 by passing over the articles held on said dies a moving belt or band of some moistureabsorbing material as felt or the like. This band is indicated at 25 and not only assists in drying the articles by taking up some of the entrained moisture therein but also serves to' hold the articles themselves on the heated dies 3.

The band 25 is an endless band substantially encircling the entire periphery of the'heated die carrier and in order to remove such moisture as it may have absorbed while in contact with the moist articles on the drying dies I provide for.

passing this band through a drying chamber after it has been in contact with the moist articles. For this purpose the apparatus is provided with suitable guide rolls 26 by means of which the flight of the band is so controlled as to cause the band to pass through a drying chamber 27 defined by a shroud or enclosure 28 supported over the drying dies.

With such an arrangement, the articles may be temporarily held on the drying dies as they are transferred thereto from the forming dies and before they are engaged by the band 25 by blasts of compressed air delivered thereagainst froma series of air jets 25. In addition to this function the air jets aid in drying the articles, particularly where the air is heated.

At the completion of the drying orbit the formed and dried articles may be dislodged from the drying dies and discharged into the packaging chute 28'.

In the form of my invention shown in Figs. 4 and 5 I avoid having the forming and drying dies come into actual contact with each other by forming the articles in a continuous strip or web of pulp on the forming dies, as indicated at S in Fig. i, which web is laid about the drying dies with the individual articles conformed and matched to the individual dies of the drying unit.

To accomplish this, the forming and drying units are caused to travel at such relative speeds that the individual articles exactly register with the dies of the drying die unit as they are transferred thereto. Suction, external air pressure, or a band such as shown in Fig. 3 may. be employed to assist in holding the strip of articles on the drying dies and after drying has been completed or substantially completed the strip may be severed by any suitable mechanismto separate the individual articles from each other.

For the purposes of this application I have indicated at 29 a guide through. which the strip of formed and dried articles is passed after it has completed its travel on the drying dies and at .30 a double-bladed reciprocating shear cooperating with stationary shear blocks 31' whereby the individual articles are successively severed from the strip in such manner that the connecting portions of the web itself are trimmed away from the article. The shear 30 may be pivoted at 31 and may be actuated from the shaft of the forming die carrier by means of the cam lever 32 and cam 33 on said shaft, the individual articles A when severed from the strip dropping into the packaging chute 34. I 1

Various other modifications in method and apparatus may all be resorted to within the spirit and scope of my invention as defined by the ap-' pended claims.

What I therefore claim and desire to secure by Letters Patent is:

1. The method of continuously molding and drying pulp articles which consists in die molding the articles from liquid pulp on a rotating series of forming dies, in rotating in orbitally intersecting relation thereto a timed series of pressing and drying dies onto which the articles are directly transferred from the forming dies, and in passing a heated moisture-absorption band over the formed articles on said pressing and drying die series to retain them on the dies and to assist in drying them while in orbit.

2. The method of continuously molding and drying pulp articles which consists in die molding the articles from liquid pulp on a rotating series of forming dies, in rotating in orbitally intersecting relation thereto a timed series of pressing and drying dies onto which the articles are directly transferred from the forming dies, and in passing a heated moisture-absorption band over the formed articles on said pressing and drying die series to retain them on the dies and to assist in drying them while in orbit. in continuously drying the moisture-loaded portion of said band after contact with the moist articles on said pressingand drying dieseries.

3. The method of continuously molding and drying pulp articles which consists in die molding the articles from liquid pulp on a rotating series of forming dies, in rotating in orbitally intersecting relation thereto a timed series of pressing and drying dies onto which the articles are directly transferred from the forming dies, and in passing a heated moisture-absorption band over the formed articles on said pressing and drying die series to retain them on the dies and to assist in drying them while in orbit, and in directing air under pressure against the articles as they are transferred from the forming dies to the pressing and drying dies to retain them on said pressing and drying die series until engaged by said band and to assist in drying them.

4. The method of continuously molding and drying pulp articles which consists in die molding the articles from liquid pulp on a rotating series of forming dies, in rotating in orbitally intersecting relation thereto a timed series of pressing and drying dies onto which the articles are directly transferred from the forming dies, and in passing a heated, moisture-absorption band over the formed articles on said pressing and drying die series to retain them on the dies and to assist in drying them while in orbit, in continuously drying the moisture-loaded portion of said band after contact with the moist articles on said pressing and drying die series, and in directing air under pressure against the articles as they are transferred from the forming dies to the pressing and drying dies to retain them on said pressing and drying die series until engaged by said band and to assist in drying them.

5. The method of molding pulp articles which consists in rotating 2. die carrier having a plurality of forming and collecting dies past a pulp deposition supply, in rotating in intercyclic relation thereto a timed pressing and drying die series onto which the formed articles are directly transferred, in maintaining said last-named dies at drying temperature during their orbit to effect drying of the articles thereon while in orbit, and in stripping the formed and dried articles from said pressing and drying dies adjacent the end 0 the drying orbit.

6. The method of molding pulp articles which consists in rotating in intercyclic relation to each other a timed series of forming dies on which the articles are formed as a continuous web and a timed series of pressing dies onto which'such web is continuously laid with the formed articles cen-' tered on the pressing dies, and in severing the individual articles from the web at the completion of the pressing die orbit.

'7. The method of molding'pulp articles which consists in rotating in intercyclic relation to each other a timed series of forming dies on which the articles are formed as a continuous web and a timed series of pressing dies onto which such web is continuously laid with the formed articles centered on the pressing dies, in heating said pressing dies to dry the web thereon while in orbit, and in severing the individual articles from the web at the completion of the pressing die orbit.

8. In pulp molding apparatus, a series of movable forming dies adapted for successive move ment past a pulp deposition supply, a series of receiving dies adapted for movement in an intercyclic orbit with that of the forming dies and onto which the formed articles are directly transferred from said forming dies, and means for heating said receiving dies to eifect drying of the articles thereon while in orbit.

9. In pulp molding apparatus, a series of movable forming diesadapted for successive movement past a pulp deposition supply, a series of receiving dies adapted for movement in an in-v .tercyclic orbit with that of the forming dies and onto which the formed articles are directly transferred as a continuous web from said forming dies, and means for successively cutting the individual articles from the web at the completion of their orbit on the receiving dies.

10. In pulp molding apparatus, a series of movable forming dies adapated for successive movement past a pulp deposition supply, a series of receiving dies adapted for movement in an intercyclic orbit with that of the forming dies and onto which the formed articles are directly transferred as a continuous web from said forming dies, means for heating said receiving dies to effect drying of the web thereon while in orbit,'and means for successively cutting the individual articles from the web at the completion of their orbit on the receiving dies.

11. In pulp molding apparatus, a series of 135 forming dies and a series of receiving dies rotating in timed intercyclic relation to each other and onto which receiving dies the formed articles are directly transferred from the forming dies, and a moisture-absorption band movable over the formed articles on said receiving dies to retain them on the dies and to assist in drying them while in orbit.

12. In pulp molding apparatus, a series of forming dies and a series of receiving dies'rotating in timed intercyclic relation to each other and onto which receiving dies the formed articles are directly transferred from the forming dies, and a moisture-absorption band movable over the formed articles on said receiving dies 15% to retain them on the dies and to assist in drying them while in orbit, and means for directing air under pressure against the articles as they are transferred fromthe forming dies to the receiving dies to retain them on the receiving dies until engaged by said band and to assist in drying them.

13. In pulp molding apparatus, a series of forming dies and a series of receiving dies rotating in timed intercyclic relation to each other and onto whichreceiving dies the formed articles are directly transferred from the forming dies, and a moisture-absorption band movable over the formedarticles on said receiving dies to retain them on the dies and to assist in drying them while in orbit, and means for continuously drying the moisture-laden portion of.

said band after contact with the moist articles on said receiving die series.

14. In the method of drying die molded pulp articles while such articles are disposed on moving dies, the step which consists in passing a heated moistureabsorption band over the moist articles while they are on such moving dies whereby both to retain them on the dies and to assist in drying them while the dies are in motion.

15'. In the method of drying die molded pulp articles while such articles are disposed on moving dies, the step which consists in passing a heated moisture-absorption band over the moist articles while they are on such moving dies whereby both to retain them on the dies and to assist in drying them while the dies are in motion, and in continuously drying the moistureloaded portion of said band after contact with the moist articles on such dies.

16. In pulp molding apparatus, a forming'die shaft and a receiving die shaft, both of said shafts being mounted for continuous rotationabout fixed axes, a carrier mounted on said forming die shaft and carrying a series of forming dies, a

carrier mounted on said receiving die shaft andcarrying .a series of receiving dies, said carriers rotating in orbitally intersecting relation to each other whereby the articles formed on said forming dies may be directly transferred to said receiving dies, and means for heating said receiving dies to effect drying of the formed articles there on while in orbit. Y

17. In pulp molding apparatus, a forming die shaft and a receiving die shaft, both of said shafts being mounted for continuous rotation about fixed axes, a carrier mounted on saidforming die shaft and carrying a series of forming dies, a carrier mounted on said receiving die shaft and carrying a series of receiving dies, said carrier for the receiving dies being of considerably greater diameter than that for the forming dies whereby the articles on said receiving dies are maintained in 30 orbit on said dies for a time which is sufllciently long to enable them to be substantially thoroughly dried, said carriers rotating in orbitally intersecting relation to each other whereby the articles formed on said forming dies may be directly 5 transferred to said receiving dies, and means for heating said receiving dies to effect drying of the formed articles thereon while in orbit.

18. Apparatus for molding pulp articles comprising a pair of members rotatable on parallel, spaced axes, a series of circumferentially spaced forming dies carried by one member to dip into pulp stock and to have articles partially formed thereon, a series of circumferentially spaced article receiving dies carried by the other member, means for intermittently rotating the members in timed relationship to bring the dies of the respective series successively into alinement with each other and to effect a pause in their rotation each time a pair of the dies become alined, and 199 means for moving at least one of the dies of the alined pair towards the other die of the pair during each pause in, the rotation of the members to causethe article to'be pressed and shaped between the dies.

19. Apparatus as set forth in claim 18 including means for-effecting transfer of the articles from the forming dies to the receiving dies.

20. Apparatus for molding pulp articles comprising a pair of members rotatable on parallel, spaced axes, a series of circumferentially spaced forming dies carried by one member to dip into pulp stock and to have articles partially formed thereon, a series of circumferentially spaced article receiving dies carried by the other member, means for intermittently rotating the members in timed relationship to bring the dies of the respective series successively into alinement with each other and to effect a pause in their rotation each time a pair of the dies become alined, and 3 means for moving one of the members towards the other during each pause in the rotation of the members to cause the articles to be pressed and shaped between the alined dies. 1

21. Apparatus as set forth in claim 20 including means for effecting transfer of the articles from the forming dies to the receiving dies IVIERLE P. CHAPLIN. 

